Wet-bulb thermometer



Sept. 15, l 925.

T. H. RHoADs WET BULB THERMOMETER 2 sheets-sheet 1 Filed Feb. 5, 1924 I 557 H'5, 0?"nqga Sept. 15, 1925.

T. H. RHOADS WET BULB '1HERNIOMETER- Filed Feb; 5,

%1924 2 Shun-Shoot 2 u Q Q M u T N RB o n -1- W Q :L v g Ufi i W QN r Q Patented Sept. 15, 1925. I

uurrso -LS1TAT'ES THOJNIAS H. RHOAZDS, OF PHILADELPHIA SCHVIARTZ, INCORPORATED, 035 PHILADELPHIA, BENNSYLVHNIA, A 1CORBOBA- TI'ON 0F PENNSYLVA NLA.

Application filed February To all whom it may concern:

Be it known that I, THOMAS H. RI-IOADS, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certain Improvements in VVet-Bulb Thermometers, of which the following is a specification.

My invention relates to certain improvements in means for moistening the sensitive bulb of a wet bulb thermometer used in controlling the humidity in driers and other apparatus.

One object of my invention is to provide means whereby the wick, which extends over the sensitive bulb of the apparatus, is supplied with water length.

A further object of the invention is to provide means for tempering the water so that it will be substantially the same temperature as the compartment in which it is located, and also to provide means for regulating the flow of water to the wick.

In the accompanying drawings:

Fig. 1 is a perspective View of my i1nproved device for moistening the wick of a wet bulb thermometer;

Fig. 2 is a plan view of the apparatus;

Fig. 3 is a side view; and

Fig. 4 is a transverse sectional view on the line 4%, Fig. 3.

Referring to the drawings, 1 is a water box, which is mounted in a drying chamber of a drying apparatus in the present instance. This water box has a central dis charge opening 2, which is connected to a waste pipe 3. Surrounding the opening is a wall 1, which maintains the Water in the box at a given height. This wall is surrounded by a casing 5 of wire gauze.

6 designates a wet bulb thermometer supported by standards 7 that project from the bottom of the box. 8 designates a Water supply pipe, which is located HIlJOVG the wet bulb thermometer and secured to each end of the casing by clamp plates 9 and 10. The pipe 8 has a series of small perforations 11 in the under side.

Extending over the wet bulb thermometer 6 is a sheet of fabric 12, which forms a wick. The ends of the Wick extend into the water in the box 1 and it is also moistened by the jets of water escaping from the pipe 8. The pipe 8 is connected to a uniformly throughout its 5,1924. Serial No. 690,749. l

supply pipe 13. "The supply pipe is-located in-the drying chamber of the drying apparatus. The length of pipe in" the chamber is such that the water passing out of the pipe is approximately the temperature of the air in the drier.

In the pipe 13 is a shut-off cock 14: and a strainer 15 of any suitable construction. At the end of the pipe 8 is a regulating angle valve 16, having a handle 17, and an outlet 18 that discharges into the box 1. By providing a. regulating valve at the end of the pipe 8, the flow of water can be regulated so that there will be an even flow of water through the perforations at a low pressure, which saturates the wick thoroughly without destroying the sensitiveness of the instruments connected with the ap paratus.

This construction also prevents any fiuctuations in the volume or pressure of the incoming water affecting the flow of water through the perforations.

In operating the apparatus, the cook 14 is opened approximately half way. The valve 16 is opened so that a certain proportion of the water will escape through the'valve and into the box. This reduces the pressure in the perforated pipeto a low degree and the water drops out of the perforated pipe uniformly along its entire length;

Any change in the pressure of the incoming water, or any stoppage in the perforations, will not affect the uniformity of the pressure of the water in the perforated pipe between the cock and the valve. 1

The water escaping from the valve keeps the water in the box at the level of the overflow so that both ends of the wick are immersed in the water. By dropping the water continuously on the wick, the wick is kept clean and free of dust so that the capillary flow of the water is not interrupted.

If, for any reason, the perforations in the pipe become clogged, or dirty, it is only necessary to close the valve 16 and to turn the cock 14: wide open. This will blow out the dirt, or other obstructions, in the perforations.

At the side of the box 1 are two brackets 19, which are shaped to support a dry bulb thermometer 20.

I claim:

1. The combination of a box having an outthermometer, moistened by Water passing through the perforations in the pipe; and

a valve, at the end of the pipe, discharging into the box.

2. The combination of a box having an outlet and a wall surrounding the outlet; a wet bulb thermometer supported above the box; a flat Wick extending over the thermometer and having its ends in the water in the box; and a perforated pipe above the thermometer arranged to discharge water onto the wick, said pipe hav ing a stop cock and provided with a valve at its end beyond the perforations, said valve discharging into the box.

3. The combination of a box arranged to contain water; a centrally located outlet for the box; a wet bulb thermometer located above the box; a wick extending over the thermometer and into the box on each side of the outlet; a water pipe having an opening through which water is supplied to the wick; and a screen surrounding the outlet of the box and extending upwards in the space between the two ends of the wick.

THOMAS H. RHOADS. 

